Retail power and gas heavyweights Kansai Electric Power, or Kepco, and Osaka Gas are locked in a struggle for dominance in the Kansai region — which includes Osaka, the nation's second-biggest city, and boasts an economy nearly the size of South Korea's.
After the 2011 Fukushima nuclear disaster, the country's power monopoly system — in place for nearly 70 years — was partially dismantled in 2016, followed by the liberalization of the retail gas market a year later.
Hundreds of new power sellers soon arrived on the scene, some with just a few dozen accounts.